Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Mar. 01, 2022	Jun. 30, 2021
Cover page [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Document Transition Report	false
Entity File Number	001-37661
Entity Registrant Name	SMARTFINANCIAL INC.
Entity Incorporation, State or Country Code	TN
Entity Tax Identification Number	62-1173944
Entity Address, Address Line One	5401 Kingston Pike, Suite 600
Entity Address, City or Town	Knoxville
Entity Address, State or Province	TN
City Area Code	865
Entity Address, Postal Zip Code	37919
Local Phone Number	437-5700
Title of 12(b) Security	Common Stock, par value $1.00 per share
Trading Symbol	SMBK
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float				$ 329.3
Entity Common Stock, Shares Outstanding			16,888,848
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Central Index Key	0001038773
Auditor Name	BKD, LLP	Dixon Hughes Goodman LLP
Auditor Firm ID	686	57
Auditor Location	Louisville, Kentucky	Atlanta, Georgia
Current Fiscal Year End Date	--12-31
ICFR Auditor Attestation Flag	true